delete-package deletes package from all package system data structures. If the operation is successful, delete-package returns true, otherwise nil. The effect of delete-package is that the name and nicknames of package cease to be recognized package names. The package object is still a package (i.e., packagep is true of it) but package-name returns nil. The consequences of deleting the COMMON-LISP package or the KEYWORD package are undefined. The consequences of invoking any other package operation on package once it has been deleted are unspecified. In particular, the consequences of invoking find-symbol, intern and other functions that look for a symbol name in a package are unspecified if they are called with *package* bound to the deleted package or with the deleted package as an argument.